What is the Zika virus?

What pregnant women need to know

News about a mysterious, tropical virus called Zika and its link to severe birth defects and newborn deaths abroad may be worrisome for many – especially pregnant women or those who are thinking about getting pregnant. The U.S Centers for Disease Control and Prevention has issued a first-of-its-kind travel alert recommending that pregnant women avoid countries where Zika has spread, and world health officials have declared a global emergency to control the Zika virus.

A small number of cases have recently been reported in the U.S. If you’re pregnant or have a loved one who is, you may understandably be concerned.

What is Zika virus?

Zika is a mosquito-borne virus related to dengue, yellow fever and the West Nile virus. The most common means to get this infection is from a mosquito bite in a region where the virus is currently being spread.

The most common symptoms are usually mild, including fever, rash, joint pain, or conjunctivitis (eye irritation). Not all patients with the Zika infection will have symptoms; only 80% will show the signs.

Brazil reported an outbreak in May and since then the virus has primarily spread in Latin American and Caribbean countries.

Who is most at risk?

What we know: Anyone who is living in or traveling to an area where the Zika virus is found who has not already been infected is at risk, including pregnant women.

The virus is most often transmitted through a mosquito but can also be spread through sexual intercourse from a partner who is infected (who travelled to an area of risk).

All pregnant woman who have traveled to any of these countries are at risk. In addition, pregnant women who have partners who have traveled to the risk areas identified by the CDC are at risk if they have unprotected intercourse.

What we don’t know: While pregnant women have been the focus of concern because of the potential to pass the virus to the fetus, we don’t know if women are more likely to get an infection just because they are pregnant.

What are the risks to a fetus?

What we know: Although the Zika virus rarely causes significant illness in adults, the effects could be severe and irreversible for the fetus of a pregnant woman who is infected. The Zika virus has recently been associated with an increased number of babies born with microcephaly (which causes an abnormally small head and is associated with brain damage), mostly in Brazil, but cases have also been reported around the world in women who traveled to areas where mosquitos transmit the infection.

What we don’t know: Unfortunately, there are still many unknowns. We don’t know how likely it is for a fetus to be affected by the virus if the mother has it. We also don’t know the full spectrum of potential outcomes. It is possible that there could be no impact, or that babies could be very mildly affected if their mother has an infection. In other cases, the consequences could be profound, impacting the child’s ability to function independently. We don’t know if the infection behaves differently in the presence of other factors like nutrition or environment. We assume the infection is worse early in pregnancy but we don’t know whether the stage of pregnancy is absolutely linked to how babies are affected.

Some newborn deaths and miscarriages abroad have also been associated with the virus.

If you are pregnant

At the present time, there is no treatment available for the Zika virus and the recommendations focus on prevention. Women who are pregnant should avoid traveling to any of the areas listed by the CDC. If travel is required, they are advised to limit exposure to mosquito environments such as forests and marshes and use insect repellent, wear long sleeves and pants, and stay in places with air conditioning.

If you have traveled to an affected region during pregnancy and are concerned, contact your primary care provider to discuss best next steps. Depending on several factors, your doctor may recommend you receive diagnostic and fetal testing to evaluate your baby’s health and development.

Dr. Marjorie Treadwell is the director of the Fetal Diagnosis Center at the University of Michigan and a maternal and fetal medicine expert. Her clinical specialties include high-risk pregnancies, genetic counseling, fetal diagnosis and therapy, education and teaching in these areas.

University of Michigan Von Voigtlander Women’s Hospital opened in December 2011, offering women a state-of-the-art place to welcome their babies to the world in the most caring and comfortable way possible. From private rooms to birthing tubs, each feature was designed around mom and baby’s every need. Learn more at www.umwomenshealth.org.

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